Biology Exam Iii Mb Questions

Front 1

What type of reaction breaks down the bonds that join the phosphate groups in an ATP molecule?

Back 1

hydrolysis (involves breaking bonds with the addition of water)

Front 2

The most common energy carrier molecule in living organisms is:

Back 2

ATP

Front 3

A "high energy" bond in an ATP molecule is located between:

Back 3

two phosphate groups

Front 4

Which molecule functions in the short term storage of energy?

Back 4

adenosine triphosphate

Front 5

most enzymes are ______.

Back 5

proteins

Front 6

enzymes work by ______.

Back 6

reducing EA (energy of activation)

Front 7

an enzyme ______.

Back 7

is an organic catalyst (enzymes are proteins that behave as catalysts)

Front 8

What name is given to the reactants in an enzymatically catalyzed reaction?

Back 8

substrate

Front 9

As a result of its involvement in a reaction, an enzyme ______.

Back 9

is unchanged

Front 10

Which of the following lowers the activation energy of a biochemical reaction?

Back 10

catalysts

Front 11

Which of the following functions as a biological catalyst?

Back 11

enzyme

Front 12

animals have enzymes that break apart starch molecules but not cellulose, despite the fact that both are made up of glucose subunits. Which enzyme characteristic BEST explains this?

Back 12

Enzymes are highly specific

Front 13

What is the ultimate source of energy for almost all forms of life on earth?

Back 13

solar energy

Front 14

Most enzymes do not work if the temperature is raised too much. Why is this?

Back 14

enzymes denature at higher temperatures (incorrect temperature, pH, and salt concentrations cause an enzyme to change shape)

Front 15

The metabolism of a cell is the sum of all its chemical reactions. True or False?

Back 15

True

Front 16

energy that is not converted to useful energy is usually given off as:

Back 16

heat

Front 17

Which of these equations best summarizes photosynthesis?

Back 17

6 CO2+6 H20 --> C6H12O6+6 O2

Front 18

The light reactions of photosynthesis use ____ and produce ____.

Back 18

water....NADPH (during the light reactions, water is split to produce oxygen. Excited electrons from water join with NADP+ to produce NADPH

Front 19

What is the purpose of a cuticle on a leaf?

Back 19

to prevent water loss (the was cuticle makes the leaf waterproof, to preven water from leaving by evaporation. The oil on your skin performs a similar function)

Front 20

How is O2 involved in photosynthesis?

Back 20

O2 is a product of the light reactions. (O2 is produced when water is consumed in the light reactions.)

Front 21

Before photosynthesis evolved, _____ was rare in the earths atmosphere.

Back 21

O2

Front 22

The products of photosynthesis are:

Back 22

glucose and oxygen

Front 23

All of the following compounds are necessary constituents for photosynthesis EXCEPT:

Back 23

NADP

Front 24

The cellular organelle that is responsible for photosynthetic activity is the:

Back 24

chloroplast

Front 25

_____ has a longer wavelength than ______.

Back 25

Red....green

Front 26

You place a plant in a transparent box made of greenish-yellow plastic. How does this affect photosynthesis for the plant?

Back 26

None of the plant pigments will be able to absorb the light. Photosynthesis will stop. (none of the major pigments absorb at this wavelength)

Front 27

Why do plants leaves appear green?

Back 27

the chlorophyll in leaves reflects green light

Front 28

Why do plants produce O2?

Back 28

because O2 is produced as a by-product when the plant creates H+ ions and free electrons from water

Front 29

Where are the electrons used in a photosystem II found at the very end of the light reactions?

Back 29

in NADPH (the electrons and a few of the hydrogen ions released from water in photosystem II are bound to NADP+ to form molecules of NADPH)

Front 30

The energy source in photosynthesis is:

Back 30

visible light

Front 31

Suppose that you are experimenting with different types of lighting for your indoor green plants. Which of the following colors of light will be most effective?

Back 31

red-blue

Front 32

Light reactions produce:

Back 32

ATP, NADPH, and O2

Front 33

Where does the O2 released during photosynthesis come from?

Back 33

H2O

Front 34

During the process of photosynthesis, solar energy is converted to:

Back 34

chemical energy

Front 35

The light reactions of photosynthesis result in which of the following?

Back 35

synthesis of ATP

Front 36

The energy of the movement of electrons down a concentration gradient via electron transport within chloroplasts and mitochondria is used to generate molecules of:

Back 36

ATP

Front 37

Suppose you are studying photosynthesis in a research lab. You grow your plants in a chamber with a source of water that has a radioactively labeled oxygen atom. What photosynthetic product will be radioactive?

Back 37

O2 gas

Front 38

The NADPH required for carbon dioxide fixation is formed:

Back 38

during the light reactions

Front 39

The primary function of the light reactions of photosynthesis is to:

Back 39

produce energy-rich ATP and NADPH

Front 40

Which of the following provides O2 as an end product?

Back 40

light reaction

Front 41

why do chloroplasts make energy carriers during the light reactions?

Back 41

to provide energy for the synthesis of sugar. (sugar synthesis is endergonic and requires the energy in ATP and NADPH to proceed)

Front 42

What structural feature of a leaf enables it to obtain CO2 from the air?

Back 42

stomata

Front 43

All of the following factors influence the rate of photosynthesis EXCEPT:

Back 43

atmosperic N2 levels

Front 44

All of the following compounds are necessary constituents for photosynthesis EXCEPT:

Back 44

oxygen

Front 45

The pigment(s) that absorb light energy to drive photosynthesis is/are:

Back 45

chlorophyll and carotenoids

Front 46

The ATP and NADPH synthesized during the light reactions are:

Back 46

dissolved in the stomata

Front 47

Carbon fixation involves the addition of carbon dioxide to _____.

Back 47

RuBP (in the calvin cycle, carbon dioxide is added to RuBP)

Front 48

after 3-PGA is phosphorylated, it is reduced by _____.

Back 48

NADPH

Front 49

How many carbon dioxide molecules must be added to RuBP to make a single molecule of glucose?

Back 49

6 (6 carbon dioxide molecules are required to produce two G3P molecules, which can be combined to make one glucose molecule)

Front 50

in the calvin cycle, how many ATP molecules are required to regenerate RuBP from five G3P molecules?

Back 50

3

Front 51

In which of the following organelles does photosynthesis take place?

Back 51

chloroplast

Front 52

What connects the two photosystems in the light reactions?

Back 52

an electron transport chain

Front 53

What two molecules are produced by the light reactions and used to power the calvin cycle?

Back 53

ATP and NADPH

Front 54

What provides electrons for the light reactions?

Back 54

H20

Front 55

What provides the carbon atoms that are incorporated into sugar molecules in the calvin cycle?

Back 55

Carbon dioxide (CO2)

Front 56

what transports electrons from the light reactions to the calvin cycle?

Back 56

NADPH

Front 57

The light reactions take place in the _______ and the calvin cycle takes place in the ______.

Back 57

Thylakoids; stroma

Front 58

The term "cycle" is used to describe the calvin cycle because:

Back 58

the process begins and ends with RuBP

Front 59

Which of the following occurs during the calvin cycle of photosynthesis?

Back 59

carbon dioxide is converted to chemicals that can be used to make sugars.

Front 60

In the C3 pathway, where does the carbon come from to form glucose?

Back 60

atmospheric CO2

Front 61

Which of the following is NOT true of chlorophyll?

Back 61

it is found in mitochondria

Front 62

The role of water in photosynthesis is to:

Back 62

provide electrons

Front 63

The energy of the movement of electrons down a concentration gradient via electron transport within the thylakoid membrane is used to generate:

Back 63

ATP

Front 64

Many plants have evolved leaves that have adjustable pores, called ______, which allow for gas exchange and water loss.

Back 64

stomata

Front 65

Carbon dioxide is required in the light reactions of photosynthesis. True or False?

Back 65

False

Front 66

Which of the following is a source of electrons that green plants use for reduction reactions?

Back 66

H2O

Front 67

Glucose synthesis during photosynthesis requires that:

Back 67

the products of energy-capturing reactions must be available

Front 68

All of the following are part of the Calvin cycle EXCEPT:

Back 68

generation of ATP

Front 69

ATP is required during which of the following reactions?

Back 69

The calvin cycle only